Eyeglass holders that may be attached to a hat or cap are known. U.S. Pat. No. 4,636,048 to Jones describes a frame, which may be worn under a hat with a provision for mounting a pair of eyeglasses such that the eyeglasses do not rest on the bridge of the nose or on the ears. The eyeglasses may be moved in one of three mutually perpendicular directions—up and down, sideways and back and forth with respect to the user's face. The eyeglasses may be pivoted up and down as well.
However, Jones suffers from several disadvantages. The frame attaches to and fits under the head liner of the hat and touches the forehead of the user. The contact of the frame with the user's skin may be uncomfortable, and particularly on hot days, sweaty. The hat must be removed from the user's head in order to adjust or remove the frame. The eyeglasses attach to the frame in a pivotal manner. This may cause the eyeglasses to swivel during use, thereby moving them out of focus. Indeed, the three-dimensional linear adjustments may move during routine walking, and become a nuisance to the user.